RE: Am I wasting my time?
Shurbs and smaller trees are excellent sources of cover and possibly forage as well, though I'm not familiar with many eastern shrub species. If you provide superior cover with forage and water available nearby, deer will retreat to your property at the first sign of pressure from the other land. However, if you allow that many hunters on your property per day they will quickly be killed or run off so I would further limit the pressure if you truly want to provide a "core" area for them.